At the present time header platforms are sometimes constructed to extend transversely of the direction of travel of a harvesting machine, and a header platform is provided with a pair of co-axial augers, one having a left-hand flight and ther other a right-hand flight, the augers being driven so that a crop after having been cut by the comb of the header platform and moved onto the platform is transported to a central location. At the central location, the crop is urged rearwardly by the action of the spiral augers and/or retractable fingers, and is then transported by an elevator, usually a slat elevator which, in the trade, is termed a "broad elevator", and this elevates the crop into the threshing drum of the machine. For the relevant prior art, the reader may refer to the U.S. Pat. Nos. 4,177,626 ST. McNAUGHT; 4,282,703 WILSON; and German Pat. No. 32 31771 DEERE.
One of the main difficulties which is encountered with existing header platforms is that the crop is moved onto the header platform in a substantially even flow, and transported across the platform at a substantially even speed and therefore tends to bunch in front of the broad elevator. In some instances the crop becomes so congested that its flow stops, so that the operator has to significantly slow the speed of the harvesting machine down to overcome this build-up problem.